Tumblr post:

Harry showing Fred and George old Muggle movies. Fred and George jumping onto the table in the Great Hall and yelling for a food fight. Platters magically refilling so that there's no end in sight. Ravenclaw getting way too into it and building a trebuchet. Hufflepuff being surprisingly good at finding just who to hit to antagonise any house in order to keep things going. Gryffindor getting into an all out war with Slytherin. Magic being used at first but then it's just the satisfaction of throwing with your hands and dumping food on your friends. The entire room freezing and not saying a word when McGonagall gets a pie in the face. The entire room breaking into a bigger war when they realise Dumbledore was the one who hit her.

I can't find out who posted this, just saw a photo on Google Images.

HP fandom!